The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Powertrain control systems include a plurality of modules that require a certain amount of engine torque to operate properly. For example, an automatic transmission control module may need to momentarily reduce torque from the engine in order to change transmission gears. Another example may be an air conditioning clutch control module that needs engine torque to be increased a moment prior to engaging an air conditioning compressor clutch. The engine torque increase helps maintain a constant engine speed when the compressor clutch engages, particularly when the engine is idling.
In the prior art these various modules affect torque actuators directly. For example, the automatic transmission control module may retard a spark advance to the engine to reduce the engine torque during the shift. Similarly, the air conditioning clutch control module may increase the spark advance to increase the engine torque during the moment prior to engaging the compressor clutch.
As vehicle powertrain systems include more modules and more actuators that affect torque, the architecture of the prior art becomes cumbersome to maintain and undesirably difficult to troubleshoot. As an example of more actuators, hybrid vehicles include an engine and an electric motor that provide torque. Integrating the hybrid vehicle powertrain to existing torque-modifying modules can be undesirably cumbersome with the existing powertrain control architecture.